package com.mzw.singleton.type1;

public class SingletonTest01 {

	public static void main(String[] args) {
		// 测试
		Singleton instance = Singleton.getInstance();
		Singleton instance2 = Singleton.getInstance();
		System.out.println(instance == instance2); // true
		System.out.println("instance.hashCode=" + instance.hashCode());
		System.out.println("instance2.hashCode=" + instance2.hashCode());
	}

}

//饿汉式(静态变量)

class Singleton {

	// 1. 构造器私有化, 外部能new
	private Singleton() {

	}

	// 2.本类内部创建对象实例
	private final static Singleton instance = new Singleton();

	// 3. 提供一个公有的静态方法，返回实例对象
	public static Singleton getInstance() {
		return instance;
	}

}